#define   _CRT_SECURE_NO_WARNINGS 1
char* my_strncat(char* destination, const char* source, size_t num)
{

	assert(destination && source);
	char* des = destination;
	while (*destination != '\0')
	{
		destination++;
	}
	while (num)
	{
		num--;
		if ((*destination = *source) != '\0')
		{
			destination++;
			source++;
		}
		else
		{
			break;
		}
	}
	*destination = '\0';
	return des;
}